U.S. Pat. No. 3,529,009 is related to a process wherein an aldehyde or ketone will undergo a condensation reaction with 2,2-dimethyl-4-cyanobutyraldehyde in the presence of a basic catalyst. In the case of acetone, in the presence of solid potassium hydroxide as a catalyst the compound 5,5-dimethyl-7-cyanoheptene-3-one-2 can be obtained in a yield of 61.1%. According to U.S. Pat. No. 2,409,086, the 2,2-dimethyl-4-cyanobutyraldehyde required for this reaction can be prepared from isobutyraldehyde and acrylonitrile by means of an alkaline catalyst with a yield of 35-40% of the theoretical yield.
Thus, the prior art processes for reacting isobutyraldehyde, acrylonitrile, and acetone to form unsaturated cyanocarbonyl compounds are impractical because of the inefficiency of the processes and the resulting cost.
The discovery of the invention is in the use of catalysts which can give a much higher yield in the preparation of such unsaturated cyanocarbonyl compounds. Thus, the invention is an improvement in the prior art processes for preparing unsaturated cyanocarbonyl compounds.